The background description provided herein is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent it is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure.
Today, a wide variety of computing devices, including many portable devices, support software applications that display digital maps (“mapping applications”). Some of these mapping applications are interactive and provide users with the ability to acquire useful information such as a route to a particular destination. The route may include one or more map elements, e.g., roads or paths that are rendered from two-dimensional (2D) map data and displayed to the viewer. The 2D map data does not include elevation information and the map elements are presented in a plane format. However, the plane format does not provide the viewer with information associated with the vertical relationship of the map elements with nearby structures, vegetation, or undulating terrain.
Other computer-based mapping applications provide users with life-like interactive scenery using three-dimensional (3D) map data, which may incorporate 3D geometry of the scenery and photographs of the structures, roads, vegetation, and terrain in the scenery. The data defining 3D geometry can be a set of vertices interconnected by edges such as 3D mesh, for example. Photographs or other images are used to “texture” the 3D geometry. The 3D map data typically is defined in a 3D coordinate system rather than in a 2D coordinate system of a 2D map.